Image-forming devices such as laser printers have conventionally been provided with a developer cartridge detachably mounted therein for supplying a developer to the surface of a photosensitive drum in the image-forming device.
The developer cartridge is commonly configured of a casing for accommodating developer, and a developing roller rotatably supported in the casing for carrying developer within the casing. The casing also has an elongated opening formed therein. The developing roller is disposed so that a portion of the roller is exposed through the opening to confront the surface of a photosensitive drum disposed in the image-forming device. As the developing roller rotates, developer from the casing carried on the surface of the developing roller comes into contact with the surface of the photosensitive drum. At this time, the developer is attracted to an electrostatic latent image formed on the surface of the photosensitive drum in order to develop the image into a developer image. Subsequently, the developer image is transferred onto a sheet of paper, forming an image on the paper.
This type of developer cartridge has been conventionally provided with sealing members disposed between each end of the developing roller and the casing to prevent developer from leaking therethrough. When the sealing member are fixed to the casing with double-sided tape or adhesive, remnants of the double-sided tape or adhesive remain on the casing after the sealing members are peeled therefrom. Accordingly, extra effort is required when recycling (reusing) the developing cartridge as the sealing members are replaced with new members.
Therefore, Japanese unexamined patent application publication No. HEI-9-269657 proposes a technique for mounting sealing members on the housing of the developing device. According to this technique, fitting parts are formed in the housing such that the sealing members can be fittingly inserted into the fitting parts. Protruding parts extending in a direction parallel to the axial direction of the developing roller (a direction orthogonal to the rotating direction of the developing roller) are formed on each fitting part to prevent the sealing members from shifting from the mounted position as the developing roller rotates.
However, in the proposed structure described above, since the sealing members are not fixed to the fitting parts with double-sided tape or adhesive, a gap may be formed between the sealing member and the fitting part as the developing roller rotates, risking the chance that developer may enter this gap and leak out of the housing along the protruding parts.